The use of fossil fuel as the combustible fuel in engines results in the combustion products of carbon monoxide, carbon dioxide, water vapor, smoke and particulate, unburned hydrocarbons, nitrogen oxides and sulfur oxides. Of these above products carbon dioxide and water vapor are considered normal and unobjectionable. In most applications, governmental imposed regulations are restricting the amount of pollutants being emitted in the exhaust gases. Additionally, during start-up, many engines, create white smoke which is considered a nuisance.
During the starting mode and especially during cold starting, past practice has been to apply current from the battery to the glow plugs for a given period of time and increase the amount of fuel during initial cranking of the engine. This practice results in drainage of the battery, poor mixing, incomplete burning and excess white smoke being emitted from the combustion chamber. As the heat of combustion increases, the efficiency of mixing fuel and air increases and the amount of white smoke is reduced and eventually eliminated.
Attempts to reduce white smoke and increase starting efficiencies include the use of external starting aids. These starting aids have included combustion aids, such as, ether starting aids and/or intake air heater. When using the above aids, the normal procedure for starting also includes a provision to increase the amount of fuel supplied to the combustion chamber. This increase of fuel supplied to the combustion chamber many time exceeds the amount of fueling for rated engine power by up to 25 percent. This is traditionally necessary since combustion is very poor at starting conditions, and only a portion of the fuel is burned. The reminder of the fuel is not burned, and is seen as excessive white smoke. Thus, these starting methods contribute to excess fuel consumption.
The present invention is directed to overcoming one or more of the problems as set forth above.